A DNA microarray can be used to detect several types of nucleic acid sequences. In some implementations, the DNA microarray includes a substrate having strands of probe nucleic acid sequences. When a solution having unknown target nucleic acid sequences is applied to the microarray, the probe nucleic acid sequences on the substrate can bind to target complementary nucleic acid sequences in the solution. The target sequences can be labeled with fluorophores, and the probe-target pairs can be detected by detecting fluorescence emissions. The identity of the target sequences can be determined based on the positions of the detected fluorescence emissions on the microarray.